Ethylene and ROS Signaling Are Key Regulators of Lateral Root Development under Salt Stress in Tomato
Authors: Rahmati Ishka, M., Zhao, J., Sussman, H., Mohanty, D., Craft, E., Yu, L., Pineros, M., Tester, M., Kawa, D., Mittler, R., Nelson, A., Fei, Z., Julkowska, M. M.
The study examined salt-induced alterations in root system architecture across a diverse panel of wild and cultivated tomato accessions, identifying tolerant varieties with distinct lateral root strategies. By combining Bulk Segregant Analysis of an F2 population with GWAS, the authors pinpointed 22 candidate genes, further narrowing to two key regulators through RNA‑Seq and functional assays involving ethylene and ROS profiling. These findings reveal genetic targets for improving salt resilience in tomato root development.
The study investigated how Arabidopsis thaliana SR protein kinases (AtSRPKs) regulate alternative RNA splicing by using chemical inhibitors of SRPK activity. Inhibition with SPHINX31 and SRPIN340 caused reduced root growth and loss of root hairs, accompanied by widespread changes in splicing and phosphorylation of genes linked to root development and other cellular processes. Multi‑omics analysis (transcriptomics and phosphoproteomics) revealed that AtSRPKs modulate diverse splicing factors and affect the splicing landscape of numerous pathways.
The study investigates the role of the Arabidopsis transcription factor AtMYB93 in sulfur (S) signaling and root development, revealing that AtMYB93 mutants exhibit altered expression of S transport and metabolism genes and increased shoot S levels, while tomato plants overexpressing SlMYB93 show reduced shoot S. Transcriptomic profiling, elemental analysis, and promoter activity assays indicate that AtMYB93 contributes to root responses to S deprivation, though functional redundancy masks clear phenotypic effects on lateral and adventitious root formation.
The study examined how genetic variation among 181 wheat (Triticum aestivum) lines influences root endophytic fungal communities using ITS2 metabarcoding. Heritability estimates and GWAS identified 11 QTLs linked to fungal clade composition, highlighting genetic control of mycobiota, especially for biotrophic AMF. These findings suggest breeding can be used to modulate beneficial root-fungal associations.
The study surveyed vegetative water use and life‑history traits across Arabidopsis thaliana ecotypes in both controlled and outdoor environments to assess how climatic history shapes water‑use strategies. Trait‑climate correlations and genome‑wide association analyses uncovered that ecotypes from warmer regions exhibit higher water use, and identified MYB59 as a key gene whose temperature‑linked alleles affect water consumption, a finding validated using myb59 mutants. These results indicate that temperature‑driven adaptive differentiation partly explains intraspecific water‑use variation.
The study investigates the Arabidopsis ribosomal protein RPS6A and its role in auxin‑related root growth, revealing that rps6a mutants display shortened primary roots, fewer lateral roots, and defective vasculature that are not rescued by exogenous auxin. Cell biological observations and global transcriptome profiling show weakened auxin signaling and reduced levels of PIN auxin transporters in the mutant, indicating a non‑canonical function of the ribosomal subunit in auxin pathways.
Genetic control of the leaf ionome in pearl millet and correlation with root and agromorphological traits
Authors: Nakombo-Gbassault, P., Arenas, S., Affortit, P., Faye, A., Flis, P., Sine, B., Moukouanga, D., Gantet, P., Kosh Komba, E., Kane, N., Bennett, M., Wells, D., Cubry, P., Bailey, E., Vigouroux, Y., Grondin, A., Laplaze, L.
The study performed ionomic profiling and genome-wide association studies on a diverse panel of pearl millet infield across two seasons to uncover genetic factors controlling nutrient acquisition. Soil analyses revealed stable depth-dependent patterns for phosphorus and zinc, while leaf ion concentrations showed high heritability and associations with root and agronomic traits. Integrating GWAS with gene expression data identified candidate ion transport/homeostasis genes for breeding nutrient-efficient, climate-resilient millet.